Linux file system directories

Essential directories on a Linux file system
Binaries (executables):
 * /bin/
 * /sbin/
 * /usr/bin/

Configuration:
 * /etc/
 * /etc/default/ (Make a link called /etc/AAA_etcdefault linking to /etc/default on Linux systems you install to remind you /etc/default is not directory of a single programming.)